Delhi Metro completes tunnelling work on Phase 4 of Golden Line project

The Tughlakabad-Aerocity corridor alone includes 19.343 km of underground sections, the statement said.

The Delhi Metro Rail Corporation has completed tunnelling work on Phase 4 of the Golden Line project between Kishangarh and Vasant Kunj stations, which is part of the Tughlakabad-Aerocity corridor.

According to the Delhi Metro Rail Corporation (DMRC), the tunnel boring machine (TBM) successfully broke through at the Vasant Kunj station site in the presence of Union Minister of Housing and Urban Affairs and Power, Manohar Lal Khattar, and Tokhan Sahu, Minister of State for Housing and Urban Affairs.

A 91-metre-long TBM completed the excavation of a 1,550-metre tunnel at Vasant Kunj station. Two parallel circular tunnels are being built for up and down movement on this stretch. The second tunnel is expected to be completed by June, a statement issued by the DMRC said. The newly-built tunnel located at an average depth of 23 metres consists of 1,107 tunnel rings, each with an inner diameter of 5.8 metres, the statement said.

The tunnel was built using the earth pressure balancing method, a widely-used tunnelling technique. Its walls are lined with precast concrete tunnel rings, cast at a fully-mechanised facility in Mundka, the statement said. To ensure durability and early strength, these concrete segments were treated using a steam curing system, it added.

As part of the approved Phase 4 expansion, the DMRC is constructing 40.109 km of underground Metro lines. The Tughlakabad-Aerocity corridor alone includes 19.343 km of underground sections, the statement said.